It has become the practice in recent times to exploit solar radiation for the purpose of collecting energy for heating spaces and water supplies. Solar collectors of various types of construction are known. In general, these collectors are included in the roof surfaces of the buildings. However, rules and restrictions in force in various municipalities prevent the installation of solar roof collectors. In other cases such collectors might detract from the architectural appearance of the buildings.
It is also known in the art to install solar collectors on the walls of buildings which have southern exposure, i.e., at vertical surfaces. Such solar collectors are generally useful only for commercial and industrial applications for aesthetic reasons.